[Kiwami]

Additional buttons which play the background music from the show (+ the theme song of course) when pressed would be epic, I know the CSM Decade Driver had that. Otherwise, I think they may use some die-cast metal in certain parts to give it more heft and paint it in better, fewer toy-ish colors.

As far as Lockseeds go, I can see them including the basic four (Orange, Banana, Grape & Melon) as updated versions with diecast + more individual sounds such as the catchphrases of the characters. Plus the faceplates for each Rider.

And ideally it should be compatible with the millions of DX Lockseeds which are already out there, I don't know how past CSM releases handled something like this though.

But yes, a CSM Sengoku Driver is on the top of my want-list as far as non-SHF Rider-merch goes, I hope they make one eventually.